Late Radiation Outcomes of Patients with Newly Diagnosed Glioblastoma Treated with Accelerated Hyperfractionated Radiotherapy and Temozolomide

Abstract

OBJECTIVEThis study aimed to evaluate the late radiation outcomes in patients with glioblastoma who were treated with accelerated hyperfractionated radiotherapy (AHRT) and concurrent plus adjuvant temozolomide (TMZ). 2006 and 2007, 32 consecutive patients with glioblastoma were treated with AHRT and TMZ. The total dose of 66 Gy was administered in 33 fractions within 6 weeks. In phase I, PTV1 received 40 Gy (2 Gy per fraction, five times per week). In phase II, 26 Gy was delivered to PTV2 by adding a second daily fraction at intervals of 8 hours once every 3 days. All patients received chemotherapy according to the Stupp protocol. Toxicities were evaluated based on the CTCAE v3.0. METHODS Between RESULTSThe median follow-up period was 18 months. A total of 28 patients completed the planned radiotherapy schedule, and 20 patients received six cycles of adjuvant TMZ. Median overall survival (OS) and progression-free survival (PFS) were 17 and 10 months, respectively. In univariate analysis, age, performance status, and RPA classes III-IV were found significant for OS. Multivariate analysis showed that six cycles of TMZ administration affected both OS and PFS. Late grade-4 central nervous system (CNS) toxicities were observed in five patients. CONCLUSIONIt was observed that it is both feasible and effective to administer AHRT with TMZ in a selected group of patients. It provides better short-term survival advantage than the standard treatment regimen. Authorship contributions: Concept -R.M., M.A., Ş.A.E.; Design -R.M., Ş.A.E., M.A.; Supervision -R.M., M.A.; Materials -Ş.A.E., R.M., M.A.; Data collection &/or processing -Ş.A.E.; Analysis and/or interpretation -Ş.A.E., R.M.; Literature search -Ş.A.E.; Writing -Ş.A.E., R.M.; Critical review -R.M., M.A.